In the construction of the railway or any part thereof the Companymay deviate vertically from the level shown on the deposited section toany extent not exceeding 0.50 metres upwards or downwards or to suchfurther extent as the Secretary of State may approve:

Provided that where the railway crosses the road the Company shallnot deviate vertically from the level shown on the deposited section toany extent beyond 10 millimetres upwards or downwards.